OMAE2003-37397 TESTS ON DYNAMIC ICE-STRUCTURE INTERACION

ABSTRACT This paper addresses the problem of ice induced vibration of offshore structures. Compliant structures having vertical ice walls may suffer from very severe vibrations. Several theories have been proposed to predict these vibrations. However, physical details of this phenomenon are not fully understood. Conical structures are deemed to be less sensitive to vibrations. Recent full-scale measurements made in the Bohai Bay indicate that also these structures my experience excessive vibrations caused by ice. Indentation tests were done at the ARCTEC laboratory at the Hamburg Ship Model Basin, Hamburg to clarify details of ice induced vibration. Sheets of columnar grained saline ice was used in the tests. The parameters that were varied included the structure's compliance and damping, indentation velocity and the structural geometry at the water line. The paper provides tests results that were obtained using vertical and conical model structures